Ratchet locking mechanism for threaded fastener

ABSTRACT

A fastening device including a fastener having a head portion and an elongated threaded body portion extending axially from the head portion. The threaded body portion includes opposing flat sections. A lock washer has a lower surface with an array of radially extending engagement teeth. The lock washer also defines an axial aperture for receiving the fastener. The axial aperture has two flat inner surfaces for cooperating with the two flat sections of the threaded body portion to prevent relative rotation of the washer and threaded body portion. A threaded lock nut mates with the threaded body portion. The lock nut has an upper surface with at least one cantilevered pawl members for ratcheted engagement with the array of radially extending engagement teeth of the lock washer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Patent ApplicationNo. 61/403,332 filed Sep. 14, 2010, which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject invention is directed generally to fasteners, and moreparticularly, to a ratcheting locking mechanism for threaded fasteners.

2. Background of the Related Art

Threaded fasteners designed to lock male and female threaded componentstogether are well known in the art and include, for example, lockwashers, blind thread bores filled with resilient inserts and screwthread profiles that deform when tightened. Fasteners with self-lockingaccessories such as cotter pins and lock wires are also known. Otherexamples of self-locking threaded fasteners are disclosed in U.S. Pat.No. 5,460,468 to DiStacio on Oct. 24, 1995; U.S. Pat. No. 5,538,378 toVan der Drift on Jul. 23, 1996; and U.S. Pat. No. 5,713,708 to Van derDrift et al. on Feb. 3, 1998, each of which is incorporated herein byreference.

SUMMARY OF THE INVENTION

One embodiment of the subject technology is directed to a fasteningdevice including a fastener having a head portion and an elongatedthreaded body portion extending axially from the head portion. Thethreaded body portion includes at least one longitudinally extendingflat section. The fastening device also includes a lock washer havingopposed upper and lower surfaces, wherein the lower surface has an arrayof radially extending engagement teeth. The lock washer also forms anaxial aperture for receiving the threaded body portion of the fastener.The axial aperture has at least one flat inner surface cooperating withthe at least one longitudinally extending flat section of the threadedbody portion to prevent relative rotation of the washer and threadedbody portion. The fastening device further includes a threaded lock nutfor rotatably mating with the threaded body portion. The lock nut hasopposed upper and lower surfaces. The upper surface of the threaded locknut has at least one flexible pawl member for ratcheted engagement withthe array of radially extending engagement teeth on the lower surface ofthe lock washer.

In another embodiment, the subject technology is directed to a fasteningdevice including a fastener having a head portion and an elongatedthreaded body portion extending axially from the head portion. A lockmember has a lower surface with a plurality of ratchet teeth. The lockmember couples to the body portion for axial movement but is fixedrotationally. A threaded lock nut rotatably mates with the threaded bodyportion. The lock nut has an upper surface having at least one pawltooth for engagement with the plurality of ratchet teeth. The lockmember may have an axial aperture having at least one flat inner surfacecooperating with the at least one longitudinally extending flat sectionof the threaded body portion. The lock member may be integral with thehead portion. In one embodiment, the fastening device includes a platedefining a recess, wherein the lock member couples into the recess to befixed rotationally.

In still another embodiment, the subject technology is directed to afastening device including a fastener having a head portion and anelongated threaded body portion extending axially from the head portion.At least one fastener tooth couples to the fastener in a rotationallyfixed manner. A locking structure has at least one locking tooth forratchet engagement with the at least one fastener tooth. The at leastone fastener tooth may be on a distal end of a pawl arm extending fromthe head portion or on a lock washer that is keyed to the fastener. Theat least one fastener tooth may be a plurality of ratchet teeth. The atleast one locking tooth may also be on a distal end of a pawl armextending from the locking structure. Alternatively, the lockingstructure is a plate having an axial recess and the at least one lockingtooth is a plurality of radially extending ratchet teeth facing a lowersurface of the head portion.

Additional aspects and advantages of the present disclosure will becomereadily apparent to those skilled in this art from the followingdetailed description, wherein only exemplary embodiments of the presentdisclosure are shown and described, simply by way of illustration of thebest mode contemplated for carrying out the present disclosure. As willbe realized, the present disclosure is capable of other and differentembodiments, and its several details are capable of modifications invarious obvious respects, all without departing from the disclosure.Accordingly, the drawings and description are to be regarded asillustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those having ordinary skill in the art to which the subjectinvention pertains will more readily understand how to make and use thefastening device of the subject invention, preferred embodiments thereofwill be described in detail hereinbelow with reference to the followingdrawings.

FIG. 1 is a side elevational view of the fastening device of the subjecttechnology in an assembled condition, wherein the lock washer and locknut are positioned on the body of the fastener.

FIG. 2 is a perspective view of the fastening device of the subjecttechnology, with the lock washer and lock nut axially aligned andseparated from the fastener body for ease of illustration.

FIG. 3 is a perspective view of the fastening device of the subjecttechnology, as viewed from above, with the lock washer and locking nutaxially separated and displaced from the fastener body for ease ofillustration.

FIG. 4 is a perspective view of the fastening device of the subjecttechnology, as viewed from below, with the lock washer and locking nutaxially separated and displaced from the fastener body for ease ofillustration.

FIG. 5 is an end view of a plurality of configurations of elongatedthreaded body portions for use with fastening devices of the subjecttechnology.

FIG. 6 is a side view of another fastening device of the subjecttechnology assembled to fixedly retain to exemplary plate structures.

FIG. 7 is a bottom view of the fastening device of FIG. 6.

FIG. 8 is a sectional view taken along line “8”-“8” of FIG. 7.

FIG. 9 is an enlarged detailed view of the area in circle “9” of FIG. 6.

FIG. 10 is a top perspective view of the fastening device of FIG. 6,with the lock washer and locking nut axially aligned and separated fromthe fastener body for ease of illustration.

FIG. 11 is a bottom perspective view of the fastening device of FIG. 6,with the threaded body portion extending through a plate and the lockwasher and lock nut axially aligned and separated from the fastener bodyfor ease of illustration.

FIG. 12 is a side view of another fastening device of the subjecttechnology assembled to fixedly retain to exemplary plate structures.

FIG. 13 is an enlarged detailed view of the area in circle “13” of FIG.12.

FIG. 14 is a top perspective view of the fastening device of FIG. 12,with the lock washer and locking nut axially aligned and separated fromthe fastener body for ease of illustration.

FIG. 15 is a bottom perspective view of the fastening device of FIG. 12,with the plate, the lock washer, and the lock nut axially aligned andseparated from the fastener body for ease of illustration.

FIG. 16a is a perspective view of a tool for assembling and/ordisassembling the fastening device of FIG. 12.

FIG. 16b is an enlarged detailed view of the area in circle “16 b” ofFIG. 16 a.

FIG. 17 is a top perspective view of still another fastening device withthe lock washer and locking nut axially aligned and separated from thefastener body for ease of illustration.

FIG. 18 is a bottom perspective view of the fastening device of FIG. 17,with the lock washer, and the lock nut axially aligned and separatedfrom the fastener body for ease of illustration.

FIG. 19a is a top view of a locking nut of the fastening device of FIG.17.

FIG. 19b is a cross-sectional view of a locking nut of the fasteningdevice of FIG. 17.

FIG. 20 is a top perspective view of yet another fastening device of thesubject technology utilizing a lock plate.

FIG. 21 is a bottom perspective view of the fastening device of FIG. 20.

FIG. 22 is a top perspective view of yet still another fastening devicewith the pawl integral to the head of the threaded fastener inaccordance with the subject technology.

FIG. 23 is a side view of a threaded fastener with the ratchet integralthereto for the fastening device of FIG. 22.

FIG. 24a is a top view of a plate structure with the ratchet integralthereto for the fastening device of FIG. 22.

FIG. 24b is a cross-sectional side view of the plate structure of FIG.24a taken along line “24 b”-“24 b”.

FIG. 25 is a bottom perspective view of yet still another fastener withthe pawl integral to the head thereof for a radial engagementconfiguration in accordance with the subject technology.

FIG. 26 is a top view of a plate structure with the ratchet integralthereto for use with the fastener of FIG. 25.

FIG. 27a is a bottom perspective view of yet still another fastener withthe pawl integral to the head thereof for a radial engagementconfiguration in accordance with the subject technology.

FIG. 27b is a top view of the fastener of FIG. 27 a.

FIG. 28a is a top view of a plate structure with the ratchet integralthereto for use with the fastener of FIG. 27 a.

FIG. 28b is a sectional view of the plate structure of FIG. 28a takenalong line “28 b”-“28 b”.

FIG. 28c is a sectional perspective view of the plate structure of FIG.28 a.

FIG. 29 is a top perspective view of yet still another fastening devicealigned with a driving tool for inserting and removing the fastener inaccordance with the subject technology.

FIG. 30a is a perspective view of the fastener of FIG. 29.

FIG. 30b is a side view of the fastener of FIG. 29.

FIG. 30c is a top view of the fastener of FIG. 29.

FIG. 30d is an enlarged perspective view of the area in circle “30 d” ofthe fastener in FIG. 30 a.

FIG. 30e is a sectional view of the fastener of FIG. 30b taken alongline “30 e”-“30 e”.

FIG. 31a is a perspective view of the plate structure of FIG. 29.

FIG. 31b is a top view of the plate structure of FIG. 31 a.

FIG. 31c is a sectional view of the plate structure of FIG. 31b takenalong line “31 c”-“31 c”.

FIG. 32a is a perspective view of the driving tool of FIG. 29.

FIG. 32b is an enlarged perspective view of the area in circle “32 a” ofthe driving tool in FIG. 32 a.

FIG. 32c is a top view of the driving tool of FIG. 29.

FIG. 32d is a side view of the driving tool of FIG. 29.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present disclosure overcomes many of the prior art problemsassociated with threaded fasteners. In general, threaded fasteners areused to fixedly connect two or more pieces in a variety of applicationssuch as, without limitation, with surgical implants, industrialapplications, and building applications. Among other features andbenefits, the disclosed ratchet locking mechanisms for threadedfasteners facilitate quick and easy installation while providing areliably secured tightness with the ability to remove the fastener ifdesired. The advantages, and other features of the technology disclosedherein, will become more readily apparent to those having ordinary skillin the art from the following detailed description of certain preferredembodiments taken in conjunction with the drawings which set forthrepresentative embodiments of the present invention and wherein likereference numerals identify similar structural elements.

All relative descriptions herein such as upward, downward, left, right,up, down, length, height, width, thickness and the like are withreference to the Figures, and not meant in a limiting sense.Additionally, the illustrated embodiments can be understood as providingexemplary features of varying detail of certain embodiments, andtherefore, features, components, modules, elements, and/or aspects ofthe illustrations can be otherwise combined, interconnected, sequenced,separated, interchanged, positioned, and/or rearranged withoutmaterially departing from the disclosed fastener assemblies.Additionally, the shapes and sizes of components are also exemplary andcan be altered without materially affecting or limiting the disclosedtechnology.

Referring now to FIG. 1, a fastening device constructed in accordancewith a preferred embodiment of the subject invention and designatedgenerally by reference numeral 10. Fastening device 10 includes athreaded fastener 12 in the form of a carriage bolt or the like, whichincludes an elongated threaded body portion 14 extending from a slottedhead portion 16. Those skilled in the art will readily appreciate thatthe head portion 16 of fastener 12 could take any conventional formknown in the art including, for example, a hexagonal head.

With additional reference to FIGS. 2 through 4, fastening device 10further includes an annular lock washer 30 having opposed upper andlower surfaces 32 a, 32 b, and an axial aperture 34 for receiving thethreaded body portion 14 of fastener 12. It is envisioned that the lockwasher 30 is a split washer defining a radial gap 35. However, the lockwasher 30 may be a continuous ring. The threaded body portion 14includes a pair of diametrically opposed, longitudinally extending flatsections 14 a, 14 b and the axial aperture 34 of lock washer 30 includesa pair of diametrically opposed flat surfaces 34 a, 34 b. Thelongitudinally extending flat sections 14 a, 14 b of the threaded bodyportion 14 and the flat surfaces 34 a, 34 b of aperture 34 cooperate toinhibit rotational movement of the lock washer 30 relative to thethreaded body portion 14, while permitting axial movement of the lockwasher 30 relative to the threaded body portion 14 during placement ofthe fastening device 10 in a structure. The lower surface 32 b of lockwasher 30 includes an array of circumferentially disposed, radiallyextending engagement teeth 38, effectively defining an annular rack orratchet gear. Each tooth 38 is triangular in shape and, preferably,substantially a right triangle with a hypotenuse 38 a facing generallyaxially and a leg 38 b being substantially parallel to the threaded bodyportion 14 when engaged.

Fastening device 10 further includes a locking nut 50 that is threadablyassociated with the threaded body portion 14 of fastener 12 and includesopposed upper and lower surface portions 52 a, 52 b. The upper surfaceportion 52 a of locking nut 50 includes a pair of diametrically opposed,cantilevered arcuate pawl arms 54 a, 54 b. The pawls arms 54 a, 54 bhave pawl teeth pairs 56 a, 56 b, respectively, that are configured forratcheted engagement with the array of radial engagement teeth 38 on thelower surface 32 b of lock washer 30. The lower surface portion 52 b oflock nut 50 defines a hexagonal fitting 55 for interaction with aturning tool such as a conventional wrench or socket (not shown). Itshould be readily appreciated that preventing the lock washer 30 fromrotating on the threaded body portion 14 of fastener 12, while allowingthe lock washer 30 to freely travel longitudinally on the body portion14, allows the lock nut 50 to engage the washer 30, but the nut 50cannot loosen once the ratcheting pawl arms 54 a, 54 b of the nut 50engage the radial teeth 38 of the washer 30 in a tight manner. The pawlteeth pairs 56 a, 56 b can slide across the hypotenuse 38 a of theratchet teeth 38 during tightening but are prevented from backing up byengagement with the leg 38 b of the ratchet teeth 38.

Those skilled in the art will readily appreciate that while the meansfor preventing the lock washer 30 from rotating relative to the threadedbody 14 has been illustrated and described as a pair of diametricallyopposed flat sections 14 a, 14 b on the body and corresponding flatsurfaces in the washer aperture 34, other means can also be employed toprevent rotation of the lock washer 30 relative to the threaded body 14.For example, there could be one flat section on the threaded body 14 andone flat surface in the aperture 34 of washer 30. There could be threeor more flat sections on the threaded body 14 and a corresponding numberof flat sections in the aperture 34 of the washer 30. Alternatively, thebody 14 could include one or more longitudinal concavities and one ormore corresponding convexities on the inner diameter of the washer 30.

Referring now to FIG. 5, an end view of a plurality of configurations ofelongated threaded body portions 14 for use with fastening devices isshown for further illustration. Each column 60 a-e utilizes a differentconfiguration of locking feature 64 a-e and each row 62 a-d varies thenumber of times that the locking feature is utilized. As can be seen,the threaded body portion 14 in row 62 b and column 60 a is shown inFIGS. 1-4. The locking feature 64 a is basically a flat portion that isutilized once (row 62 a, column 60 a) or repeated various times althoughfor simplicity only a maximum of four repetitions (row 62 d, column 60a) are shown. Similarly the other locking features of a circular cut(column 60 b), a groove cut (column 60 c), a wedge or keyhole cut(column 60 d), or a triangular cut (column 60 e) and the like can beutilized any number of times.

Now referring to FIG. 6, a side view of another fastening device 110 ofthe subject technology assembled is shown. As will be appreciated bythose of ordinary skill in the pertinent art, the fastening device 110utilizes similar principles to the fastening device 10 described above.Accordingly, like reference numerals preceded by the numeral “1” areused to indicate like elements. The following description is directed tothe primary differences of the fastening device 110, which in comparisonto the fastening device 10 is the use of a hex head 116 on the threadedfastener 112, a single pawl tooth 156 a, 156 b on each pawl arm 154 a,154 b of the locking nut 150, and a solid ring lock washer 130. Thefastening device 110 is shown fixedly retaining two exemplary platestructures 180 a, 180 b. It is also noted that a slot 155 to create aflexibility in the pawl arm 154 a is also relatively shorter in thefastening device 110 as compared with the fastening device 10 shownabove. FIGS. 7-11 illustrate various other views to more fullyappreciate the structure and operation of the fastening device 110.

Referring now particularly to FIG. 9, an enlarged detailed view of thearea in circle “9” of FIG. 6 is shown to illustrate the pawl tooth 156 aof the pawl arm 154 a engaged in the teeth 138 of the lock washer 130.The pawl tooth 156 a is configured to also have a leg 157 b flushagainst the leg 138 b of the corresponding ratchet tooth 138 to preventloosening of the lock nut 130. However, a hypotenuse 157 a of the pawltooth 156 a may still move forward over the hypotenuse 138 a of theratchet tooth 138 by deflection of the pawl arm 154 a into the pawl slot155. It is also envisioned that a radial hole or other feature can beprovided in the pawl teeth 156 a, 156 b so that the pawl teeth 156 a,156 b may be pushed or pulled downward into the pawl slot 155 in orderto allow the lock nut to be removed after tightening.

Now referring to FIG. 12, a side view of another fastening device 210 ofthe subject technology assembled is shown. As will be appreciated bythose of ordinary skill in the pertinent art, the fastening device 210utilizes similar principles to the fastening devices 10, 110 describedabove. Accordingly, like reference numerals preceded by the numeral “2”are used to indicate like elements. The following description isdirected to the primary difference of the fastening device 210, which incomparison to the fastening devices 10, 110 is a radial arrangement ofthe ratchet teeth 238 and pawl teeth 256 a, 256 b as opposed to a faceto face arrangement.

Referring now to FIGS. 14 and 15, top and bottom perspective views ofthe fastening device 210, with the lock washer 230 and locking nut 250axially aligned and separated from the fastener body 214, are shown,respectively. The lock washer 230 includes an optional base plate 231with which the lock washer ratchet teeth 238 are integral. The teeth 238are located on the outer circumference of the lower portion 233 of thelock washer 238.

The locking nut 250 forms a cavity 235 into which the lower portion 233of the lock washer 230 fits so that the base plate 231 rests against thelocking nut 250 and the lock washer ratchet teeth 238 are aligned withthe locking nut pawl teeth 256 a, 256 b. In one embodiment, the fitbetween the lock washer 230 and locking nut 250 is such that thecombination may be sold and treated during installation as an integralunit. In such a case, distal curved hooks 237 on the pawl arms 254 a,254 b allow using a tool (see FIG. 16a ) to splay the pawl arms 254 a,254 b radially outward during insertion of the lock washer 230. The sametool may also be utilized to splay the pawl arms 254 a, 254 b radiallyoutward in order to remove the locking nut 250 after tightening.

Referring now particularly to FIG. 13, an enlarged detailed view of thearea in circle “13” of FIG. 12 is shown to illustrate the lock washer230 and locking nut 250 after assembly and tightening of the fasteningdevice 210. When assembled, the ratchet teeth 238 and the locking nutpawl teeth 256 a, 256 b again form a ratchet and pawl that allowstightening of the fastening device 210 but prevents loosening due to theinteraction between the lock washer 230 and locking nut 250. Duringtightening, as the locking nut 250 rotates about the lock washer 230,the pawl arms 254 a, 254 b deflect radially outward to traverse acrossthe teeth 238 of the lock washer 230. However, the configuration of theratchet and pawl is such that travel only proceeds in the tighteningdirection without undue force.

Referring now to FIGS. 16a and 16b , perspective and enlarged detailedviews of a tool 270 for assembling and/or disassembling the fasteningdevice 210 are shown, respectively. The tool 270 has a shaft 276extending between a proximal handle 272 and a distal working portion274. The distal working portion 274 includes a socket aperture 278 forcoupling to the locking nut 250 in a traditional manner. The workingportion 274 also include diametrically opposed posts 279 a, 279 b thatcouple into the curved hooks 237 on the pawl arms 254 a, 254 b such thatupon loosening the locking nut 250 with the tool 270, the pawl arms 254a, 254 b are flexed radially outward to disengage the ratchet and pawlmechanism.

Now referring to FIGS. 17 and 18, top and bottom perspective explodedviews of another fastening device 310 of the subject technology areshown. As will be appreciated by those of ordinary skill in thepertinent art, the fastening device 310 utilizes similar principles tothe fastening devices 10, 110, 210 described above. Accordingly, likereference numerals preceded by the numeral “3” are used to indicate likeelements. The following description is directed to the primarydifference of the fastening device 310, which in comparison to thefastening devices 210 is a varied configuration of the locking washer330 and lock nut 350.

The lock washer 330 includes a base plate 331 with an annular wall 333extending therefrom. The lock washer ratchet teeth 338 are formed on theinner radius of the annular wall 333. Three optional flanges 335 extendfrom the lower end of the annular wall 333 to facilitate retaining thelocking nut 350 therein.

The locking nut 350 is sized to fit within the annular wall 333 of thelock washer 330 so that the lock washer ratchet teeth 338 are alignedwith the locking nut pawl teeth 356 a, 356 b. In one embodiment, theoptional flanges 335 are welded into place after assembly to permanentlyfix the lock washer 330 and locking nut 350 as an assembly.

Referring now to FIGS. 19a and 19b , top and cross-sectional views ofthe locking nut 350 are shown, respectively. It is noted that thecross-sectional view of FIG. 19b passes through the pawl arms 354 a, 354b. The locking nut 350 defines slotted apertures 351 aligned withcircular holes 353 in the pawl arms 354 a, 354 b. Consequently, aremoval tool (not shown) may include two posts that can be insertedthrough the slotted apertures 351 into the circular holes 353. As thetwo posts are moved radially inward, the pawl arms 354 a, 354 b splayradially inward to remove the pawl teeth 356 a, 356 b from the ratchetteeth 338 of the lock washer 330 in order to remove the locking nut 350after tightening.

Now referring to FIGS. 20 and 21, top and bottom perspective explodedviews of another fastening device 410 of the subject technology areshown. As will be appreciated by those of ordinary skill in thepertinent art, the fastening device 410 utilizes similar principles tothe fastening devices 10, 110, 210, 310 described above. Accordingly,like reference numerals preceded by the numeral “4” are used to indicatelike elements. The following description is directed to the primarydifference of the fastening device 410, which is incorporation offeatures to rotationally couple the plate structure 480 and the lockwasher 430.

The lock washer 430 includes ratchet teeth 438 but rather than having acylindrical circumference, the circumference is interrupted by opposingshoulders 445. The plate structure 480 forms a recess 447 sized andconfigured to receive the lock washer 430. Because of thenon-cylindrical shapes of the lock washer 430 and recess 447, the lockwasher 430 is stopped from rotational movement therein. As a result, theflat section 414 b of the threaded body portion 414 is optional. Duringdeployment, the ratchet and pawl operation between the lock washer 430and locking nut 450 occurs equally as effectively as noted above withjust the recess 447 of the plate structure 480 preventing lock washer430 rotation.

Now referring to FIG. 22, a top perspective exploded view of anotherfastening device 510 of the subject technology is shown. As will beappreciated by those of ordinary skill in the pertinent art, thefastening device 510 utilizes similar principles to the fasteningdevices 10, 110, 210, 310, 410 described above. Accordingly, likereference numerals preceded by the numeral “5” are used to indicate likeelements. The following description is directed to the primarydifference of the fastening device 510, which is incorporation of pawlarms 554 a, 554 b into the fastener head 516.

Referring additionally now to FIG. 23, a side view of the threadedfastener 512 is shown. The fastener head 516 defines the pawl arms 554a, 554 b in an outer circumference thereof. The fastener head 516 alsodefines a hexagonal axial recess 517, best seen in FIG. 22, forcooperating with an allen wrench or like driving tool (not shown).

Referring now to FIGS. 24a and 24b , top and cross-sectional views ofthe plate structure 580 are shown. The plate structure 580 incorporatesthe ratchet teeth 538 into the bottom of a recess 547. It is envisionedthat the plate structure 580 can be any shape or configuration such as abar, band, plate and the like depending upon the desired application.

Referring again to FIG. 22, the threaded body portion 514 is a selftapping design so that the fastener 512 can pass through the platestructure 580 and threadably engage a structure opposite thereto. In analternative embodiment, the threaded body portion 514 has machinethreads that mate into machine threads of the plate structure 580. Uponthe fastener head 516 reaching the ratchet teeth 538 in the platestructure 580, the teeth 556 a, 556 b of the pawl arms 554 a, 554 bengage the ratchet teeth 538 to prevent reversal of the fastener 512 inthe normal course. In an alternative embodiment, a radial hole isprovided in the pawl arms 554 a, 554 b to allow inserting a tool andpulling the pawl arms 554 a, 554 b upward to disengage the ratchet andpawl, thereby allowing reversal of the fastener 512.

Now referring to FIGS. 25 and 26, a bottom perspective exploded view ofanother fastener 612 and a top view of a plate structure 680 of thesubject technology are shown. As will be appreciated by those ofordinary skill in the pertinent art, the fastener 612 and platestructure 680 utilize similar principles to the fastening devicesdescribed above and like reference numerals preceded by the numeral “6”are used to indicate like elements. The primary differences relate toproviding the ratchet and pawl engagement in a radial manner whileincorporating the pawl arms 654 a, 654 b into the fastener head 616.

In the plate structure 680, the ratchet teeth 638 are again disposed inthe recess 647 but located in the sidewall rather than the bottom of therecess 647. The fastener head 616 is sized and configured to fit intothe recess 647 so that the pawl teeth 656 a, 656 b of the pawl arms 654a, 654 b engage with the ratchet teeth 638.

Now referring to FIGS. 27a-28c , various views of another fastener 712and a plate structure 780 of the subject technology are shown. Theprimary differences are that the pawl arms 754 a, 754 b extend radiallyoutward from the fastener head 716 and the recess 747 has a trapezoidalcross-sectional shape (best seen in FIG. 28b ). The combination of theradially extended pawl arms 754 a, 754 b within the trapezoidal recess747 may create an effective capture of the fastener head 716 therein sothat once combined, the fastener 712 is coupled to the plate structure780. A radially engaging ratchet and pawl version could equally as wellutilize the radially extended pawl arms.

Now referring to FIG. 29, a top perspective exploded view of anotherfastening device 810 being attached to an object 808 in accordance withthe subject technology is shown. The object 808 could be any size orshape and preferably includes a pilot hole 809 to facilitate easyinsertion of the fastener 812. As will be appreciated by those ofordinary skill in the pertinent art, the fastening device 810 utilizessimilar principles to the fastening devices described above and likereference numerals preceded by the numeral “8” are used to indicate likeelements. The following description is directed to the primarydifferences of the fastening device 810, which is incorporation of thepawl arms 854 a, 854 b into a rim 860 of the threaded body portion 814of the fastener 812.

Referring now to FIGS. 30a-e , various views of the fastener 812 of FIG.29 are shown in detail. The rim 860 between the head 816 and bodyportion 814 includes the pawl arms 854 a, 854 b. The pawl arms 854 a,854 b are formed by slots 855 with radially extending distal teeth 856a, 856 b. The pawl arms 854 a, 854 b also define an axial slot 862 a,862 b adjacent the teeth 856 a, 856 b. As best seen in FIG. 30e , thepawl teeth 856 a, 856 b are triangular with legs 861 a, 861 b and ahypotenuse 865 a, 865 b that engage the ratchet teeth 838.

As best seen in FIGS. 30c-e , the fastener head 816 has axial apertures864 a, 864 b that extend at least into if not through the rim 860. Theaxial apertures 864 a, 864 b also include notches 866 a, 866 b thatalign with the axial slots 862 a, 862 b on the pawl arms 854 a, 854 bthat allow the fastener 812 to be reversible as described below. In analternative embodiment, the fastener 812 does not have axial slots inthe pawl arms or notches in the apertures of the head so that thefastener is not reversible. The fastener head 816 also forms atraditional hexagonal recess 817.

Referring now to FIGS. 31a-c , various views of the plate structure 880are shown. The plate structure 880 is particularly suited to couple withthe fastener 812 to form a ratchet and pawl engagement. The recess 847is countersunk to compliment the shape of the fastener head 816. Theratchet teeth 838 are arranged vertically to interact with the pawl armteeth 856 a, 856 b during tightening of the fastener 812.

Referring now to FIGS. 32a-d various views of the driving tool 870 fortightening and removing the fastener 812 are shown. The shaft 872 ishexagonal to couple with the recess 817 of the fastener head 816. Thedriving tool 870 includes two projections 877 a, 877 b on the distalworking portion 874. Each projection 877 a, 877 b includes a tip 879 a,879 b sized to insert into the respective axial slots 862 a, 862 b ofthe pawl arms 854 a, 854 b when the projections 877 a, 877 b are fullyinserted into the axial apertures 864 a, 864 b of the fastener head 816.Once the projections 877 a, 877 b are fully inserted, the driving tool870 can be rotated to tighten or remove the fastener 812 as desired. Astandard hex tool can also be used to tighten the fastener 812 with thepawl arm teeth 856 a, 856 ratcheting on the ratchet teeth 838.

During tightening the fastener 812, the driving tool shaft 876 engagesthe fastener head 816 so that the fastener 812 can be rotated. Thefastener 812 would self tap into the object 808 and bring the rim 860into the recess 847. In an alternative embodiment, the fastener 812 hasmachine threads that mate into corresponding machine threads in object808. Similar to above, the pawl teeth 856 a, 856 b and ratchet teeth 838would interact to allow tightening but prevent loosening unless theloosening force is applied by the driving tool 870.

To remove the fastener 812, the driving tool 870 is fully inserted intothe fastener head 816 so that the tips 879 a, 879 b of the projections877 a, 877 b press into the axial slots 862 a, 862 b. As best envisionedwith respect to FIG. 30e , a counter-clockwise rotation of the drivingtool 870 would force the pawl arms 854 a, 854 b to deflect radiallyinward so that the legs 861 a, 861 b of the pawl teeth 856 a, 856 b moveradially inward until touching a sidewall 863 a, 863 b of the axialapertures 864 a, 864 b. As a result, the pawl teeth 856 a, 856 b aredisengaged from the ratchet teeth 838 and the fastener 812 is able to berotated out.

The fastening device technology described herein has unlimitedapplication in industry and other uses. Particularly advantageousapplications will involve use near motors or moving equipment in whichvibration may cause loosening of traditional fasteners such as inautomotive applications, aerospace applications, and manufacturingmachinery. The present fastening device technology is also well suitedfor medical applications such as attaching pedicle screws to spinalrods, attaching spinal plates and fracture plates, fixing artificialjoints like hips and knees, and the like.

While the subject invention has been described with respect to preferredand exemplary embodiments, those skilled in the art will readilyappreciate that various changes and/or modifications can be made to theinvention without departing from the spirit or scope of the invention asdescribed herein and as defined by the appended claims.

1. A fastening device comprising: a) a fastener having a head portion and an elongated threaded body portion extending axially from the head portion; b) a lock member having a lower surface with a plurality of ratchet teeth, the lock member coupling to the body portion for axial movement but is fixed rotationally; and c) a threaded lock nut for rotatably mating with the threaded body portion, the lock nut having an upper surface having at least one pawl tooth for ratcheted engagement with the plurality of ratchet teeth, wherein the threaded lock nut includes a curved hook disposed radially outward of the at least one pawl tooth to receive a tool for engaging and disengaging the at least one pawl tooth from ratcheted engagement with the plurality of ratchet teeth.
 2. A fastening device as recited in claim 1, wherein the lock member has an axial aperture having at least one flat inner surface cooperating with the at least one flat inner surface cooperating with the at least one longitudinally extending flat section of the threaded body portion.
 3. A fastening device as recited in claim 1, wherein the lock member is integral with the head portion.
 4. A fastening device as recited in claim 1, further comprising a plate defining a recess, wherein the lock member couples into the recess to be fixed rotationally.
 5. A fastening device as recited in claim 5, wherein the recess defines at least one flat sidewall and the lock member has at least one shoulder for coupling thereto.
 6. A fastening device comprising: a) a fastener having a head portion and an elongated threaded body portion extending axially from the head portion; b) at least one fastener tooth coupled to the fastener in a rotationally fixed manner; and c) a locking structure having at least one locking tooth for ratcheted engagement with the at least one fastener tooth, wherein the locking structure includes a curved hook disposed radially outward of the at least one locking tooth to receive a tool for engaging and disengaging the at least one locking tooth from ratcheted engagement with the at least one fastener tooth.
 7. A fastening device as recited in claim 6, wherein the at least one fastener tooth is on a distal end of a pawl arm extending from the head portion.
 8. A fastening device as recited in claim 6, wherein the at least one fastener tooth is on a lock washer being keyed to the fastener.
 9. A fastening device as recited in claim 6, wherein the at least one fastener tooth is a plurality of ratchet teeth.
 10. A fastening device as recited in claim 6, wherein the locking structure is a plate having an axial recess and the at least one locking tooth is a plurality of radially extending ratchet teeth facing a lower surface of the head portion.
 11. A fastening device as recited in claim 6, wherein the fastener includes a rim portion intermediate the head portion and the threaded body portion and the at least one fastener tooth is a pair of pawl arms with teeth incorporated into the rim portion.
 12. A fastening device as recited in claim 11, wherein the rim portion defines slots that partially define the pawl arms.
 13. A fastening device as recited in claim 11, wherein the pawl arms define axial slots adjacent the teeth.
 14. A fastening device as recited in claim 11, wherein the head portion defines axial apertures that extend at least into the rim portion.
 15. A fastening device as recited in claim 6, wherein the locking structure is a plate structure defining a recess to compliment a shape of the head portion, the recess having a plurality of ratchet teeth arranged axially to interact with the at least one fastener tooth during tightening of the fastener.
 16. A fastening device as recited in claim 6, further comprising a tool for tightening and removing the fastener, the driving tool including a pair of diametrically opposed posts on a distal working portion.
 17. A fastening device comprising: a) a fastener having a head portion and an elongated threaded body portion extending axially from the head portion, the threaded body portion including at least one longitudinally extending flat section; b) a lock washer having opposed upper and lower surfaces, the lower surface having an array of radially extending engagement teeth, the lock washer also defines an axial aperture for receiving the threaded body portion of the fastener, the aperture having at least one inner surface cooperating with the at least one longitudinally extending section of the threaded body portion to prevent relative rotation of the washer and threaded body portion; and c) a threaded lock nut for rotatably mating with the threaded body portion, the lock nut having opposed upper and lower surfaces, the upper surface of the threaded lock nut having a pair of arcuate, cantilevered pawl members for ratcheted engagement with the array of radially extending engagement teeth of the lock washer, wherein the threaded lock nut includes a curved hook disposed radially outward of at least one of the cantilevered pawl members to receive a tool for engaging and disengaging the at least one pawl cantilevered pawl member from ratcheted engagement with the radially extending engagement teeth of the lock washer.
 18. A fastening device as recited in claim 17, wherein the lock washer defines a radial gap.
 19. A fastening device as recited in claim 17, wherein the at least one inner surface is selected from the group consisting of a flat surface, a plurality of flat surfaces, a circular cut, a plurality of circular cuts, a groove cut, a plurality of groove cuts, a keyhole cut, a plurality of keyhole cuts, a triangular cut, a plurality of triangular cuts, and combinations thereof, and the at least one longitudinally extending section is selected from the group consisting of a flat section, a plurality of flat sections, a circular section, a plurality of circular sections, a groove section, a plurality of groove sections, a keyhole section, a plurality of keyhole sections, a triangular section, a plurality of triangular sections, and combinations thereof.
 20. A fastening device as recited in claim 17, wherein the fastener, the lock washer, and the threaded lock nut are adapted and configured for a medical application. 